A star near the centre of our galaxy reaches almost 3 per cent of the speed of light as it is whipped around something four million times the mass of the Sun that emits no light of its own — and tracking its orbit for nearly three decades helped two astronomers wi - Space Daily

Astronomers have tracked the orbit of the star S2 around Sagittarius A*, the supermassive black hole at the center of the Milky Way, for nearly three decades. These observations confirmed Einstein's predictions regarding gravity and mass, earning the researchers significant scientific recognition.